Net Electrical Efficiency Research Articles

Techno-economic analysis of ultra-supercritical power plants using air- and oxy-combustion circulating fluidized bed with and without CO2 capture

The adoption of oxy-combustion in a circulating fluidized bed (CFB) producing ultra-supercritical (USC) steam has been investigated to increase energy efficiency and reduce CO2 emissions of coal-fired power plants. This paper presents a techno-economic analysis for 500 MWe USC-CFB power plants with air- and oxy-combustion in the presence of CO2 capture. An amine absorber unit (AAU) and a CO2 processing unit (CPU) were used to capture CO2 in the air- and oxy-combustion power plants, respectively. The air-combustion power plant without CO2 capture (Case 1) showed the highest net electricity efficiency (46%), whereas the introduction of an AAU in the air-combustion power plant (Case 2) reduced the net efficiency to 36%. The net efficiency (39%) of the oxy-combustion power plant with CPU (Case 3) was higher than that of Case 2 owing to the recycling of hot flue gas. The levelized cost of electricity (LCOE) of Case 3 (59 $/MWh) was lower than that of Case 2 (64 $/MWh), which demonstrated that oxy-combustion was advantageous compared to air-combustion in a scenario with CO2 capture. The sensitivity analyses of the electricity price and CO2 credit showed economic situations where Cases 2 and 3 would be profitable.

Advanced part-load control strategies for the Allam cycle

The Allam Cycle is a highly regenerative oxy-combustion cycle with very promising net electrical efficiency, low expected cost and near-zero emissions (being directly suitable for carbon capture and storage). In this cycle, the CO2 produced from the oxy-combustion is recycled as temperature moderator and the excess CO2 produced can be captured and stored. In this work, a detailed part-load model of the Allam Cycle is developed considering the off-design performance maps for the compressors, pumps and the turbine. To adjust the cycle load, different part-load control strategies are devised by combining turbine partial-admission, compressor variable guide vanes (at compressor inlet and diffuser) and minimum cycle pressure variation. These control strategies are compared at various part-load conditions ranging from 90% down to 20%. The study shows that the optimal control strategy varies depending on the cycle load. Furthermore, the increase of part-load cycle efficiency using advanced control strategies can reach up to 4.71 percentage points compared to a conventional strategy employing only variable compressor guide vanes. The research shows that close-to-maximum part-load efficiency can be achieved only with the optimized adjustment of compressors guide vanes and the minimum cycle pressure, while partial admission turbine turns out to be essential at very low loads (15–30% load).

Thermoeconomic Optimization of a Hybrid Photovoltaic-Solid Oxide Fuel Cell System for Decentralized Application

A small-scale, decentralized hybrid system is proposed for autonomous operation in a commercial building (small hotel). The study attempts to provide a potential solution, which will be attractive both in terms of efficiency and economics. The proposed configuration consists of the photovoltaic (PV) and solid oxide fuel cell (SOFC) subsystems. The fuel cell subsystem is fueled with natural gas. The SOFC stack model is validated using literature data. A thermoeconomic optimization strategy, based on a genetic algorithm approach, is applied to the developed model to minimize the system lifecycle cost (LCC). Four decision variables are identified and chosen for the thermoeconomic optimization: temperature at anode inlet, temperature at cathode inlet, temperature at combustor exit, and steam-to-carbon ratio. The total capacity at design conditions is 70 and 137.5 kWe, for the PV and SOFC subsystems, respectively. After the application of the optimization process, the LCC is reduced from 1,203,266 to 1,049,984 USD. This improvement is due to the reduction of fuel consumed by the system, which also results in an increase of the average net electrical efficiency from 29.2 to 35.4%. The thermoeconomic optimization of the system increases its future viability and energy market penetration potential.

Gasifier, Solid Oxide Fuel Cell Integrated Systems for Energy Production From Wet Biomass

Nowadays, there is worldwide interest in diversifying the energy supply. In this regard, biomass is the best possible renewable organic substitute for fossil fuels. In particular, the energy content of very wet biomass, recovered with appropriate technology, could be potentially used for power generation. In addition to power generation, this technology would represent a sanitary option to improve the quality of public health and the environment. Supercritical water gasification (SCWG) is a technology applied for the conversion of wet biomass into gas. It uses the specific physical properties of water at supercritical conditions to decompose the organic matter. However, near 100% conversion, close to thermodynamic equilibrium, of real biomass into gas is not yet demonstrated. The conversion is higher at dry biomass concentrations below 10 wt.%, but at these conditions, the system is not energetically sustainable. The conversion depends on the SCWG operating conditions and the properties of the catalyst. Because of the present-day technical limitations, the conversion efficiency in SCWG is low when fed with real biomass. The net electrical efficiency of a combined system SCWG Solid Oxide Fuel Cell (SOFC), fed with faecal sludge at 15 wt.% dry biomass, reaches between 50 to 70% (thermodynamically calculated values) while utilising an SCWG designed with present day engineering gives 29-40%. The SOFC fuel utilisation influences the system efficiency significantly, as the process heat available for the heat integration dependents on fuel utilisation. The extreme operating conditions of an SCWG - based system cause technical limitations towards reaching complete conversion during gasification. An efficient and stable catalyst is not yet available catalysts at competitive costs for low-temperature SCWG of real biomass. Intensive research in different gasification – SOFC system configurations that include the integration of complementary processes, such as the electrochemical oxidation of higher hydrocarbons or the electrochemical reduction of CO2 and H2O, will increase the potential of the gasification – SOFC system for commercialisation in medium-scale in the future, and become a technology that provide economic, environmental and health benefits.

Thermodynamic modeling and parametric study of a small-scale natural gas/hydrogen-fueled gas turbine system for decentralized applications

In this study a detailed thermodynamic model of a small-scale natural gas/hydrogen-fueled gas turbine system is presented. The thermodynamic model includes both a basic thermodynamic analysis and an exergy analysis. Exergy analysis aims on the identification of exergy destruction in the various system components. Specifically, it is investigated how hydrogen addition in the fuel supply can affect exergy loss. Off-design modeling is also implemented to realistically evaluate performance at part-load operation. A parametric study is conducted to examine the effect of hydrogen ratio on system performance. The hydrogen ratio is varied from 0 to 0.9, to examine the behavior of the developed model at different hydrogen contents. The results suggest that hydrogen addition to the natural gas fuel supply can change the operational behavior of the gas turbine cycle. Although net electrical efficiency is only marginally increased as hydrogen ratio is increased (0.347 vs. 0.356), the exergetic efficiency is more significantly affected, mainly due to the reduction of combustor losses as hydrogen content increases (0.338 vs. 0.360). Also, hydrogen addition has a positive effect in terms of carbon emissions, since even a tiny hydrogen injection at a hydrogen ratio of 0.1 (on a volumetric basis) results in a 6.1% reduction in CO2 emissions, as compared to methane-only fueling. Overall, the results suggest that even a small amount of hydrogen addition to the gas turbine cycle can have a significantly positive effect in terms of system efficiency and operational cost.

Experimental study on the influence of the saline concentration in the electrical performance of a Hygroscopic cycle

The Hygroscopic cycle is a novel proprietary power cycle characterized by working with hygroscopic compounds which optimize the condensation of the turbine output steam in a steam absorber. This technology can be incorporated in any power plant that uses a Rankine cycle, obtaining higher electrical efficiency without limiting the cold sink temperature and without cooling water consumption. The novelty of this article is that Hygroscopic cycle is experimentally investigated in a test power plant with high concentrations of lithium bromide solution in water in the cooling reflux to analyze the effect on condensing temperature, condensing pressure, power output and efficiency. Mass concentration of lithium bromide in the cooling reflux stream ranges from 45 to 65%. The increase in salt concentration at the cooling reflux stream allows the condensing temperatures to be significantly increased by more than 15 °C in a Hygroscopic cycle with respect to a Rankine cycle. Results also show that it is possible to decrease the turbine outlet condensing pressures for the same condensing temperature. Thereby, as mass concentration of lithium bromide is increased the gross electric power output increases with reference to a Rankine cycle for the same condensing temperature. The minimum increments in net electric power output and electrical efficiency are 7.6% and 2.6% respectively.

Results from an industrial size biogas-fed SOFC plant (the DEMOSOFC project)

The EU-funded DEMOSOFC project aims to demonstrate the technical and economic feasibility of operating a 174 kWe Solid Oxide Fuel Cell (SOFC) in a wastewater treatment plant. The fuel for the three SOFC modules (3 × 58 kWe) is biogas, which is available on-site from the anaerobic digestion of sludge collected from treated wastewater. The integrated biogas-SOFC plant includes three main units: 1) the biogas cleaning and compression section, 2) the three SOFC power modules, and 3) the heat recovery loop. Main advantages of the proposed layout are the net electric efficiency of the SOFC, which is in the range 50–55%, and the near-zero emissions. A specific focus of the demonstration project is the deep and reliable removal of harmful biogas contaminants. The presented work is related to the design of the SOFC system integrated into the wastewater treatment plant, followed by the analysis of the first results from the plant operation. We analyzed the biogas yearly profile to determine the optimal SOFC capacity to install that is 3 SOFC modules. The rational is to maintain high the capacity factor while minimizing the number of shutdown per year (due to biogas unavailability). First results from plant operation are also presented. The first SOFC module was activated in October 2017 and the second in October 2018. The measured SOFC efficiency from compressed biogas to AC power has always been higher than 50–52%, with peaks of 56%. Dedicated emissions measurements have been performed onsite during December 2017. Results on real biogas operation show NOx < 20 mg/m3, SO2 < 8 mg/m3 (detection limits for the instrument) and PM lower than ambient air values.

Formic acid synthesis – a case study of CO2 utilization from coal direct chemical looping combustion power plant

ABSTRACT Chemical looping combustion (CLC) is an encouraging technology for hydrogen and power co-generation with efficient CO2 capture. Utilization of the captured CO2 is a much more important task to realize negative CO2 emissions. The objective of the work is to explore a case study of carbon dioxide utilization (CDU) in the form of formic acid synthesis using the captured CO2 and co-generated H2 from coal direct chemical looping (CDCL) power plant. Steady-state simulations are performed on the power and H2 co-generation CDCL plant integrated with formic acid synthesis and presented a comparison of overall performance of the CDCL plants with and without CDU integration. The simulation results revealed that the formic acid synthesis integrated CDCL plant avoids release of 62.49 kg.CO2/GJ of fuel input into the environment and utilizes the captured CO2 completely with the net electrical efficiency penalty of 5.8%.

Multi-objective optimization of a novel reversible High-Temperature Heat Pump-Organic Rankine Cycle (HTHP-ORC) for industrial low-grade waste heat recovery

Nowadays, a high amount of industrial thermal energy is still lost due to the lack of competitive solutions for energy revalorization. Facing this challenge, this paper presents a novel technology, based on a reversible High-Temperature Heat Pump (HTHP) and Organic Rankine Cycle (ORC). The proposed system recovers low-grade waste heat to generate electricity or useful heat in accordance with consumer demand. Compressor and expander semi-empirical models have been considered for the reversible system computational simulation, being HFC-245fa the working fluid selected. The built-in volume ratio and Internal Heat Exchanger (IHX) effectiveness have been optimized to reach the maximum energy efficiency in each operating condition. Although HFC-245fa exhibits energy performance attributes, its high Global Warming Potential (GWP) is an issue for climate change mitigation. Hence, multi-objective optimisation of the environmentally friendly working fluids Butane, Pentane, HFO-1336mzz(Z), R-514A, HCFO-1233zd(E) and HCFO-1224yd(Z) has been carried out. The results show that the system proposed, working with HFC-245fa, achieves a Coefficient of Performance (COP) of 2.44 for condensing temperature of 140 °C, operating in HTHP mode, whereas the ORC mode provides a net electrical efficiency of 8.7% at condensing temperature of 40 °C. Besides, HCFO-1233zd(E) and HCFO-1224yd(Z) are both appropriate alternatives for the HFC-245fa replacement. These working fluids provide a COP improvement of 9.7% and 5.8% and electrical net efficiency improvement of 2.1% and 0.8%, respectively, compared to HFC-245fa. This paper provides a reference study for further designs and developments of reversible HTHP-ORC systems used for industrial low-grade waste heat recovery.

Optimization of Anode Off-Gas Recycle Ratio for a Natural Gas-Fueled 1 kW SOFC CHP System

Anode off-gas recycle is an effective method to improve fuel utilization (Uf) and efficiency of solid oxide fuel cell (SOFC) systems. One of the key issues is to determine the optimum recycle ratio of anode off-gas, which mainly contains H2O, CO2 and unused H2, CO. In this study, a process model of a 1 kW SOFC combined heat and power (CHP) system using natural gas as fuel was established, and the effect of anode off-gas recycle ratio on the operation of the system was studied. The recycle ratio of anode off-gas used ranged from 0 to 0.5. Based on the results, the recycle ratio around 0.3 is recommended. In this case, the net electrical efficiency of the system is 54.4%, the thermal efficiency is 28.8%, the total efficiency is 83.2% (LHV), and the actual Uf is 77.1%.

Technical performance analysis of a combined cooling heating and power (CCHP) system based on solid oxide fuel cell (SOFC) technology – A building application

A circular solid oxide fuel cell (SOFC) is developed and designed to operate in a tri-generation system of combined cooling, heating, and power (CCHP). The designed system is technically analyzed and the feasibility of the proposed system, i.e. integration of the SOFC with a two-stage absorption chiller and a heating system, was evaluated. The performance of the presented system was assessed in an educational building (900 m2) in Tehran, Iran. It was shown that the net electrical energy efficiency of the SOFC with a production capacity of 120 kW is about 45%. The hybrid system reached an electrical-cooling efficiency of 58%, eletrical-heating efficiency of 60%, and the CCHP system reached an overall efficiency of nearly 60%. Economic analysis demonstrated that in spite of high efficiency values in CCHP system and significant reduction of the major contaminants, the capital recovery period was estimated to be 8.3 years.

Proposal of a thermally-driven air compressor for waste heat recovery

The industrial sector accounts for one third of the global energy use, mainly due to the energy-intensive industries. Waste heat recovery plays a major role among the advances that can lead to potential savings in these industries. The present work proposes an air compressor that generates industrial compressed air in a novel manner only by recovering heat from exhaust gases, not by consuming electric power, and employing readily available technologies transferred from other sectors. The proposed system is an externally-heated open-loop Brayton cycle operating with air in which a fraction of the compressed air from the compressor is delivered as product, while the remainder is heated up and processed in the expander. In its turn, the expander drives only the compressor and not also an electric generator as in conventional cycles. The system is simply realized combining a single- or a two-stage turbocharger from marine reciprocating engines and a recovery heat exchanger. In single-stage, it can deliver compressed air at a pressure up to 500 kPa, while in two-stage over 1000 kPa. Here, the two-stage configuration is applied to a container glass manufacturing plant and simulated accurately with the code Aspen Plus and Aspen EDR. This work demonstrates that the system could be realized with proven technology from other industrial sectors. It indicates also that 2342 m3/h of compressed air at 800 kPa can be produced from the exhaust gas at 12,000 m3/h (referred to 0 °C and 101.325 kPa) and 560 °C. The performance is affected strongly by the ambient air condition and the furnace load with variations of the compressed air rate ranging from −92% up to +52% in the extreme conditions. The intercooling power is typically around just 35% of the waste heat recovery and, in any case, always lower than 50%. The gross and net equivalent electric efficiencies are in the range 12–16% and 10–14%, respectively, similarly to conventional heat recovery power plants of same size. The performance can be further improved by employing the hot air from the expander as preheated combustion air or for cogeneration. Ultimately, with respect to conventional plants, the system is a simpler technology operating with a harmless fluid, requiring a lower cooling power and a smaller footprint.

Biomass retrofit for existing solar organic Rankine cycle power plants: Conceptual hybridization strategy and techno-economic assessment

This study aims to investigate techno-economic benefits of biomass retrofit for practical concentrated solar power (CSP) organic Rankine cycle (ORC) power plants. In this regard, technical parameters of an existing CSP-ORC plant currently running in Ottana (Italy) have been adopted for analyses. The plant consists of linear Fresnel collectors solar field, coupled with a two-tank oil-based thermal energy storage (TES) device, feeding a 630 kWe ORC plant. Fixed and modular biomass hybridization approaches were proposed for retrofit. In the fixed approach, biomass furnace constantly supplies thermal energy to ORC such that a pre-determined minimum power production is guaranteed, with or without solar thermal energy availability. In the modular approach, biomass furnace is regulated to supply balance thermal energy needed to continuously operate the ORC at its full capacity. Furthermore, beyond the biomass retrofit case study, a newly integrated design case study was introduced, with modified solar field and TES capacity. By using the meteorological conditions of Ottana, results of techno-economic performance for the retrofit case study showed that annual net electrical efficiency increases by 4–5 percent points, relative to the solar-only ORC plant. Marginal levelized cost of electricity (LCOE) of between 103 €/MWh and 109 €/MWh were obtained. Also, marginal net present value (NPV) ranges from 1.83 M€ to 3.22 M€. For the newly integrated design case study, results showed that design case with modular hybridization approach represents the highest annual net electrical efficiency, at 19.8%. For this approach, economic results showed that LCOE ranges between 130 €/MWh and 146 €/MWh. Beyond current state-of-the-art, the results obtained in this study show that biomass retrofit for existing CSP-ORC plants can lead to higher full-load operation hours and more prospective plant economics. Moreover, the implemented modular approach enables scheduled power profile to be followed, thereby enhancing plant dispatchability.

Off-design performance analysis of a novel hybrid binary geothermal-biomass power plant in extreme environmental conditions

A novel configuration of a hybrid binary geothermal biomass power plant is proposed that generates electricity through the Organic Rankine Cycle (ORC), which receives the thermal power provided by a biomass heat source through intermediate geothermal fluid. The plants are located in regions with extreme environmental conditions where water is not available, making the use of air-cooled condensers in the ORC necessary, and the seasonal variations of the ambient air temperature are remarkable. As a further novel aspect, the modification of the biomass mass flow rate is used to overcome the simultaneous harmful effects of a considerable reduction in the geothermal fluid temperature during the operative life of the plant and the more significant seasonal change of the ambient air temperature. Our original approach involves developing a simulation model of the proposed plant using the commercial software Aspen® to determine the energy performance in off-design conditions, i.e., in the presence of the simultaneous changes of the biomass flow rate, ambient air temperature and geothermal fluid temperature. The biomass flow rate is controlled to maximize the net electric power or net thermodynamic efficiency of the plant with varying ambient air and geothermal fluid temperatures. In comparison to the first operating mode, the second enables a saving of the biomass used annually in the range of 28.3%–42.6%, corresponding to the maximum and minimum geothermal fluid temperature, respectively, with the resulting detrimental effect on the yearly produced electric energy in the range of 9%–23.6%.

Methods to Improve Energy Conversion Efficiency of Dielectric Elastomer Generators

Dielectric elastomer generators (DEGs) are based on the electromechanical response of the dielectric elastomer film sandwiched between the compliant electrodes on each side, which are capable of converting mechanical energy from diverse sources (e.g, ocean wave) into electrical energy. In essence, DEG is a voltage up-converter using mechanical energy to increase the electrical energy of the charge on a soft capacitor. We evaluated the effect of input voltage and the pre-stretch ratios on energy conversion efficiency of DEG. With a power supply of 2.2kV and pre-stretch ratio of 2, the maximum net electrical energy density and energy conversion efficiency in a single harvesting cycle were measured to be 413 J/kg and 15.8%, respectively. The experimental results showed that, with the higher input voltage and the larger stretch ratio range, higher the energy conversion performance of DEG can be achieved.

Performance analysis of a novel SOFC-HCCI engine hybrid system coupled with metal hydride reactor for H2 addition by waste heat recovery

A novel SOFC-HCCI engine hybrid power generation system fueled with alternative fuels is proposed and modeled in this paper. The steady-state modeling shows that it is feasible to use SOFC anode off-gas as the downstream HCCI engine fuel for additional power generation under certain fuel utilization and operating temperature. Through parametric and exergy analyses, it is found that the hybrid system without additional H2 can achieve a net electrical efficiency of approximately 59% and an exergy efficiency of 57%, slightly higher than the SOFC-GT hybrid system. In this hybrid system, the components of HCCI engine and its exhaust gas dominate the exergy destruction, which contributes nearly 75% but has a relatively low contribution to the total power. Based on this, the methods of recycling exhaust gas waste heat to drive hydrogen desorption of metal hydride as H2 addition for HCCI engine and H2 recirculation for SOFC anode off-gas are suggested to significantly improve the system overall efficiency due to the consideration of thermal efficiency. The high overall efficiency up to 79.54% and fuel flexibility demonstrate that the novel hybrid system is a promising energy conversion system.

Investigations on experimental performance and system behavior of 10 kW organic Rankine cycle using scroll-type expander for low-grade heat source

In this study, experimental characteristics of a 10 kW organic Rankine cycle (ORC) with R245fa were investigated for low-grade waste heat recovery. A semi-hermetic scroll-type expander was utilized with proper lubrication. The conductive oil loop using electric heaters was to simulate low-grade heat source. The temperature and heat power of the heat source were set to 120 °C and 34–77 kW, respectively. Results showed that pressure ratio and degree of superheating exhibit high sensitivity on system performance. The trend of isentropic efficiency for expander presented decreasing with pressure ratio in rise, while pressure ratio for the inlet and outlet of the expander is larger than 4. In addition, there is a particular phenomenon existing under low pinch point temperature. Mass flow rate and pressure ratio exhibited periodic distribution with time, while the pinch point temperature is lower than 10 °C. It means that the pinch point temperature has a critical value, which leads to the supply of heat source not under stable situation for low pinch point temperature. This phenomenon of thermal fluctuation may result in reduce useful life for system components. The maximum measured electrical power, net thermal efficiency and net electricity efficiency are 6.2 kW, 8.9% and 7.9%, respectively. As a consequence, the electricity generation and net electricity efficiency could be further raised while the simulated heat power increases based on the present efforts. The present work demonstrates the potential of scroll-type expander for the small-scaled ORC applications, such as industrial waste heat recovery, geothermal energy.

Techno-Economic Comparison of Combined Cycle Power Plants with Pre-Combustion Co2 Capture Via Two Different Reforming Methods: Chemical Looping Reforming and Gas Switching Reforming

This paper focuses on the techno-economic comparison of gas-fired combined cycle power plants with CO2 capture and two reforming methods, chemical looping reforming (CLR) and gas-switching reforming (GSR). The overall processes are denoted as CLR-CC and GSR-CC respectively. The net electrical efficiency of the CLR-CC and GSR-CC is 42.1% and 46.2% respectively. Anyhow, with improvements in the gas turbine configuration, the net electrical efficiency improves by 2.5%. GSR-CC has a higher CO2 avoidance (>95%). The levelised cost of electricity (LCOE) for CLR-CC is lower than that of GSR-CC for based load operation of the power plant. Anyhow, GSR-CC provides flexibility in terms of output, electricity or pure H2. The capital requirement in the GSR-CC is higher due to the requirement of multiple standalone reactors to maintain a steady flow of the syngas produced from the GSR. The LCOE of both the processes is sensitive to the fuel cost. Further improvements in the GSR-CC process can make the process competitive to post- combustion capture.

A parametric study on thermodynamic performance of a SOFC oriented hybrid energy system

In this paper, a parametric study of the performance of a SOFC system for several types of supplied fuels is carried out. A SOFC system which is assisted by some energy resources, namely biomass, solar energy and natural gas, i.e. methane, is designed in order to realize this study.This system consists of four main components which are Solid Oxide Fuel Cell (SOFC), Proton Exchange Membrane Electrolyser (PEME), Photovoltaic system (PV), and Anaerobic Digester for biogas production (AD). The system is designed by considering three fundamental operation modes which are day-time (M1), night-time (M2), and winter-time (M3), in accordance with the duration of solar irradiation period. In order to evaluate the performance of the system, comprehensive energy and exergy analyses are performed, as major system parameters are changed for the operation modes considered. In this study, maximum total energy and exergy efficiency values of 0.60 and 0.49, respectively, are achieved when the overall energy and exergy performance of the system is evaluated, at 5500 A/m2 current density for M3 operation mode among the three operation modes considered. Finally, the maximum net electrical energy and exergy efficiencies are achieved for 633 °C SOFC fuel inlet temperature and 8000 A/m2 current density, in this study.

A Distributed Generation Hybrid System for Electric Energy Boosting Fueled with Olive Industry Wastes

This paper presents the theoretical model and the simulation of a cutting edge hybrid power system composed of an externally-fired gas turbine (EFGT) coupled with an organic Rankine cycle (ORC) as a bottoming unit for the maximization of electrical power. The power plant is fed with different biomass sources from olive industry wastes (pruning, dry pomace, stones, leaves and twigs), providing more than 550 kW of electric power and a net electrical efficiency of 26.0%. These wastes were burnt directly at atmospheric pressure in an EFGT, producing 400 kW of electric power and exhaust gases at 300 °C. Ten suitable ORC working fluids have been studied to maximize the electric power generation: cyclohexane, isohexane, pentane, isopentane, neopentane, R113, R245fa, R365mfc, R1233zd and methanol. The best fluid was R1233zd, reaching 152.4 kW and 22.1% of ORC thermal efficiency; as drawback, however, R1233zd was not suitable for Combined Heat and Power CHP applications due its lower condensation temperature. Thus, despite R113 gave minor electricity production (137.5 kW) this allowed to generate additional thermal power (506.8 kW) in the way of hot water at 45 °C.